Perl

1. Perl Group 6 – Necrofantasia JosueLlamas Edward Cossio Billy Huynh  Minh Woong Lia Chua

2. Perl Programming Language • Created in 1987 by Larry Wall • Open-source • well-established programming language in the computer world. It was first established

3. Larry Wall • Born on September 27, 1954 • Graduated from Seattle Pacific University w/ degree in artificial and natural languages. • Graduate school at UC Berkeley. • a researcher, developer, and author at O'Reilly & Associates.

4. Developed Perl while working for Unysis • won the first Free Software Foundation Award for the Advancement of Free Software • International Obfuscated C Code Contest twice • Also wrote of the three virtues of computer programmers

5. Virtues • Laziness =The quality that makes you go to great effort to reduce overall energy expenditure. • Impatience =This makes you write programs that don't just react to your needs, but actually anticipate them. • Hubris =The quality that makes you write (and maintain) programs that other people won't want to say bad things about

6. Motivation for Perl • He was simply lazy • He was tired of doing everyday jobs over and over again • He wanted to have a way it to do it for him

7. Choosing a name • Larry Wall wanted it to have a name with a positive connotation. • Thought about most 4 letter words. • Even his wife Gloria • Chose Pearl but it was already taken

8. Different Versions of Perl • Perl 1.0 1987 • Perl 2 =regular expression engine, 1988 • Perl 3= added support for binary streams, 1989 • Perl 4= followed the Programming Perl book, 1991 • Perl 5= allowed modules • Perl 6= the future

9. Open Source • Its free to download. • Any one can work with it • A lot of support for it • Business can use it w/ no restrictions • Synonymous with CGI

10. Perl Programming Language

11. Perl Creation Creator Larry Wall 1987 Created to make report processing easier

12. Perl borrowed features of other languages C, AWK, Sed Larry Wall still manages Perl New version Perl 6 underdevelopment Creation

13. Design • Response to 3 big computer trends • Lower hardware prices • Rising labor costs • Improvements on compilers

14. Design • Designed for efficient computer-programmers • Designed to be useful with not so expensive hardware

15. Design • Dynamic Typing • Strings • Automatic Memory Management • Follows Theory “No built-in limits”

16. Design • Arrays • Scalars • Hashes • All have different leading sigils

17. Design • Language to get job done • Not tidy • Tolerates exception to rules

18. Design • Compiler has forgiving nature • Bugs sometimes hard to find

19. Design • Linguistic Principles • Language constructs are concise • Natural for humans to write

20. Design • No written specification • No standards for perl • None planned for Perl 5

21. Philosophy Behind Perl by Billy Huynh

22. At first the program was created to manipulate the text in order to process reports. • Now it was used for Network programming, Web Development, Graphical User Interface Development and system administration. • Perl is more of a language that “Bridges” other languages together to complete a task. • Perl is at the point where it is mostly used for programming graphics or CGI.

23. Perl provides more of a freedom to the programmers in the aspect of flexibility in getting a job done. • Similar to a Swiss Army Knife • A program that focuses on mutable data • Focuses on making easy programming, easier, and complex programs possible to program.

24. Pros and Cons by Minh Woong

25. Perl is a very flexible language Advantages • It gives programmers the freedom to develop programs and solve problems the way they want to. One of Perl’s motto is “There’s more than one way to do it.” Disadvantages • Other people might have a hard time trying to read the program, since the code are arrange differently.

26. Perl is quick and has some features that let programmers save time. • Perl’s codes are short and dense. • There are shortcuts and default for writing Perl code that would help reduce the length of the code by 10 to 20 times.

27. Examples • (1..5) = (1, 2, 3, 4, 5) • (1..10) = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10) • @10 = (1..10) • @5 = (1..5) • A list of strings can be written as: (“minh", “billy", “josue", “lia", “edward") • Or: qw(minh billyjosueliaedward)

28. Simple way to show the “Hello, world” program: sub hello { "Hello, world!\n" } print hello(); A shortcuts for the “Hello, world” program: print "Hello, world!\n"; A complex way: #!/usr/bin/perl print # This is a comment "Hello, world!\n" ; # Don't write your Perl code like this!

29. Perl is free and available in most OS. • There are thousand of Perl programs, modules, sample codes, and other useful things that people create and can be download for free online.

30. Perl is quite secure • You can prevent other people from stealing your codes by using Perl’s source filters and bytecode compilers, which render your code so that only you can execute it, and makes it unreadable by other people.

31. Major Applications developed in Perl by Lia Chua

32. Amazon.com • used Perl to develop an entire editorial production and control system • company decided to expand into online auctions in 1999 • needed to construct a prototype of a complex, robust auction site as immediately as possible • chose Perl to develop their online auction website. • because Perl is really well-suited for rapid development, they were able to build a prototype website, with full bidding functionality, up and running in a couple of weeks

33. Amazon.com • Perl enabled Lopez's group to construct a full-blown site that allows for close of auctions and customer feedback • Perl facilitated the development time by incorporating other software and utilizing existing modules rather than start from scratch

34. TERMIUMplus • a trilingual application which enables translators and terminologists to search a collection of 1.5 million entries in English, French and Spanish. • Perl enabled the developers of TERMIUMplus to provide a simple to use and enjoyable interface to the database servers. • With Perl talking to the database server's HTTP interface, they were able to obtain the required results data and then utilize Perl's power to reformat the results into something pleasing and tailored to the user's preferences.

35. eSP • an internal ordering system • banks developers chose Perl to construct a fully configurable shopping-basket ordering system. • allowed the bank branch admin staff to order technology services online instead of going through e-mail • enabled the orders to be saved, duplicated, transferred among users, and monitored as they were processed.

36. eSP • the bank has been introduced to the concept of rapid bottom-up application development using extreme programming concepts, as well as the versatility of Perl as a core development platform for web-based applications.

37. GabTown.com • Java and C was considered for Gabtown.com, however, Perl’s development time outweighed any minor benefits Java and C may have offered. • completed the GabTown.com application in just ten months, crediting Perl's development speed over compiled languages

38. Pluto • Sweden’s pension system • Sandell and Johnson's team built the application called Pluto with Perl • evaluations also indicated that Pluto was faster and more likely to succeed than the original application. • The commercial system proved difficult to customize and install despite the two years of modification by numerous developers • Pluto became the Premium Pension System's application of choice.

39. Pluto • Any doubt that a Perl-based application would be robust enough to handle a large, mission-critical, financial-batch system has been dispelled by Pluto's performance with the Swedish national pension since its launch in the fall of 2000